An operational amplifier in CMOS technology with a Class AB output stage is disclosed in a paper of A. Torralba, R. G. Carvajal, J. Martinez-Heredia and J. Ramirez-Angulo entitled “Class AB output stage for low voltage CMOS op-amps with accurate quiescent current control”, Electronic letters, 2000, Vol. 36, No. 21, pp. 1753–1754. This output stage has a pair of p-channel and n-channel output transistors series-connected between the VDD and VSS supply terminals of a power supply. The stage has two pairs of drive inputs that require a floating voltage to be applied to each pair. Although this output stage can be operated at a low supply voltage close to the transistor threshold voltage, larger supply voltages require the polarity of the floating voltage sources to be inverted.